Concrete form for pouring polygonal columns

ABSTRACT

A concrete form for pouring a polygonal column includes a plurality N of plate members arranged to form a polygonal tube having N sides, where N is an integer greater than or equal to three. The form further comprises a reinforcing framework including a plurality of ring assemblies longitudinally spaced along the tube and interconnected by a plurality of circumferentially spaced longitudinal members. Each ring assembly extends circumferentially about the tube and comprises N ring segments each having an inner surface bearing against an outer surface of a respective one of the plate members, and an outer surface formed as a circular arc. The outer surfaces of the N ring segments collectively form a substantially circular outer surface. The form also includes a plurality of clamps respectively encircling the circular outer surfaces of the ring assemblies and being releasably tightened thereabout.

BACKGROUND OF THE INVENTION

The present disclosure relates to forms for pouring concrete columns of polygonal (e.g., square or rectangular) cross-section.

Pouring a round concrete column is a relatively simple matter typically entailing the use of a round paperboard tube as a form into which the concrete is poured. The paperboard tube is stripped from the column after the concrete hardens. On the other hand, pouring a square or rectangular column requires a form of more-complicated construction. In some cases, the form can comprise a round paperboard tube having additional elements inserted into the tube to define the desired non-round cross-sectional shape for the column to be formed. This type of form can be adequate for some applications, but may not have sufficient strength and stiffness for other applications.

High-strength forms made of steel panels and frames are available, but are relatively expensive and heavy, and can be complicated to assemble at the jobsite.

BRIEF SUMMARY OF THE DISCLOSURE

The present disclosure relates to a concrete form for pouring a column of polygonal cross-section, which can be constructed from predominantly non-metallic materials and yet can achieve high strength and stiffness, and which is also relatively simple to assemble at a jobsite. In accordance with one aspect of the present disclosure, a concrete form for pouring a polygonal column comprises a plurality N of plate members arranged to form a polygonal tube having N sides, where N is an integer greater than or equal to three. The form further comprises a reinforcing framework including a plurality of ring assemblies longitudinally spaced along the tube and interconnected by a plurality of circumferentially spaced longitudinal members. Each ring assembly extends circumferentially about the tube and comprises N ring segments each having an inner surface bearing against an outer surface of a respective one of the plate members, and an outer surface formed as a circular arc. The outer surfaces of the N ring segments collectively form a substantially circular outer surface. The form also includes a plurality of clamps respectively encircling the circular outer surfaces of the ring assemblies and being releasably tightened thereabout.

In one embodiment, the inner surface of each ring segment is substantially planar and includes from one to a plurality of spaced notches therein for respectively accommodating from one to a plurality of the longitudinal members in the notches. The inner surface of each longitudinal member is substantially flush with the inner surface of the ring segment.

In accordance with one embodiment, the first plate member and a first plurality of the ring segments and longitudinal members are secured together forming a first unit, the second plate member and a second plurality of the ring segments and longitudinal members are secured together forming a second unit, the third plate member and a third plurality of the ring segments and longitudinal members are secured together forming a third unit, and the fourth plate member and a fourth plurality of the ring segments and longitudinal members are secured together forming a fourth unit. The first through fourth units are configured to releasably mate with one another at respective side edges of the units such that the tube is formed by the plate members of the units, and such that the ring segments of each unit are aligned with the ring segments of the other units.

The adjacent side edges of the units can releasably mate with one another in any suitable way. In one embodiment, one side edge of each unit defines a rabbet that receives a side edge of an adjacent one of the units so as to form a rabbet joint therebetween.

In one embodiment, each clamp comprises a band clamp that includes a least one metal band and at least one latch. In a particular embodiment, each band clamp includes separate first and second metal bands and first and second latches, the first latch comprising a first latch actuator affixed to one end of the first metal band and a first latch member affixed to one end of the second metal band, the second latch comprising a second latch actuator affixed to the opposite end of the second metal band and a second latch member affixed to the opposite end of the first metal band. The metal bands are configured to extend about one of the ring assemblies and to be secured thereabout by engaging the first latch actuator with the first latch member and the second latch actuator with the second latch member.

Advantageously, the latches comprise over-center latches. Each latch actuator comprises a base having a latch handle connected thereto so as to pivot about a first pivot axis. A latch bail has one end connected to the latch handle so as to pivot relative to the latch handle about a second pivot axis spaced from the first pivot axis, an opposite end of the latch bail being engageable with the latch member. To tighten the metal band and secure the latch, the latch handle is pivoted about the first pivot axis to cause the latch bail to draw the latch member toward the first pivot axis, until the second pivot axis passes to the over-center position.

In accordance with one embodiment, the form comprises four units for forming a square or rectangular column. However, the form can be configured to form columns of three, five, six, or more sides.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Having thus described the disclosure in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

FIG. 1 is a perspective view of a concrete form in accordance with one embodiment of the invention;

FIG. 2 is a perspective view of one unit of the concrete form;

FIG. 3 is an end elevation of the concrete form;

FIG. 4 is an enlarged fragmentary view of an over-center latch mechanism used in the concrete form;

FIG. 5 is an exploded perspective view of the concrete form; and

FIG. 6 is an exploded end elevation of the concrete form.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention now will be described more fully hereinafter with reference to the accompanying drawings in which some but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

A concrete form 100 in accordance with one embodiment of the invention is depicted in FIGS. 1 through 6. The illustrated form 100 is configured for producing a concrete column having a substantially square cross-section; however, as will become apparent, the basic concept behind the form can be adapted to the production of columns of various polygonal cross-section shapes such as triangular, quadrilateral (of which squares and rectangles are subsets), pentagonal, hexagonal, octagonal, etc. The following detailed description will focus on the quadrilateral (specifically, square) cross-section. Thus, the form 100 is made up of four units 200, 300, 400, 500 each of which defines one of the four sides of the square concrete column, the four units fitting together in mutually orthogonal fashion to form an assembly that has a substantially square channel C (FIGS. 1 and 3) extending longitudinally from one end of the form 100 to the opposite end thereof. The assembly of the four units is held together by a series of band clamps 600 that encircle the assembly.

As noted, in the illustrated embodiment, the four units 200, 300, 400, 500 are substantially identical. Accordingly, only the unit 200 will be described in detail, with primary reference to FIG. 2, since the description applies equally to the other three units. The unit 200 comprises a plate member 210 of rectangular shape in plan view. The longer dimension or length of the plate member is equal to the desired length of the form, which corresponds to the desired length of the column (although the form may be slightly longer than the column ultimately produced). The width of the plate member is approximately equal to the desired width of one side of the square column to be produced, plus the thickness of the plate member. Thus, for example, if the side of the column is to be 24 inches wide and the plate member is 1 inch thick, then the width of the plate member is 25 inches. The plate member advantageously can be formed of a non-metallic material such as plastic or wood (e.g., plywood), although the invention is not limited to any particular material.

The back side or outer surface 212 of the plate member 210 is reinforced by a reinforcing framework that includes a plurality of ring segments 220 longitudinally spaced along the plate member 210 and secured thereto by any suitable means (including but not limited to adhesive and/or fasteners). The ring segments 220 can be formed of any of various materials, including but not limited to a plastic material, a wood material (e.g., solid wood board or plywood), or other suitable material. Each ring segment 220 has an inner surface 222 that is substantially planar and bears against the outer surface 212 of the plate member 210, and an outer surface 224 formed as a circular arc. In the case of a square concrete form as illustrated, the outer surface 224 extends for approximately 90° of arc; the ring segments of forms for producing columns having a different number of sides would be modified accordingly (e.g., a form for a hexagonal column would have ring segments whose outer surface extends for approximately 60° of arc).

The reinforcing framework for the plate member 210 further comprises at least one longitudinal member 230 that is secured to the outer surface 212 of the plate member (e.g., by adhesive and/or fasteners) and extends along substantially the entire length of the plate member. The longitudinal member(s) can be formed of any suitable material, including but not limited to solid wood board, plywood, plastic, or the like. The inner surface 222 of each of the ring segments 220 has a notch that accommodates each longitudinal member 230, such that the inner surface of the longitudinally member is substantially flush with the inner surfaces of the ring segments. The longitudinal member 230 can be secured in the notch, such as by adhesive and/or fasteners.

In the illustrated embodiment, the reinforcing framework includes three longitudinal members 230, 232, 234 that are circumferentially spaced (i.e., spaced apart along the width of the plate member). The longitudinal member 230 is located at about the midpoint of the width of the plate member, the longitudinal member 232 is located adjacent one longitudinal edge of the plate member, and the longitudinal member 234 is located adjacent the other longitudinal edge of the plate member. As best seen in FIG. 6, the longitudinal member 232 overhangs the edge of the plate member 210 by an amount substantially equal to the thickness of the plate member for the unit 500 that connects with the edge of the unit 200. Advantageously, all of the plate members for the four units 200, 300, 400, 500 are substantially identical in dimensions, including thickness, and the amount of overhang is the same for all four units. The overhang, or rabbet 236 (FIG. 6), allows the units to fit together in a manner forming rabbet joints between the adjacent edges of the units, as best seen in FIG. 3.

The four units 200, 300, 400, 500 are configured such that the ring segments of the units are aligned along the circumferential direction when the units are assembled in the mutually orthogonal configuration such as shown in FIGS. 1 and 3. Four of the aligned ring segments collectively form a ring assembly that extends circumferentially about the square tube formed by the units. The circular-arc outer surfaces of the four ring segments collectively form a substantially circular outer surface. There are a plurality of these ring assemblies spaced along the length of the square tube. Although in the illustrated embodiment the ring segments are spaced uniformly along the length of the form and the longitudinal members are spaced generally uniformly about the circumference, alternatively the ring segments and/or longitudinal members can be spaced non-uniformly. For example, since the hydraulic pressure of the wet concrete in the form is highest at the bottom end of the form, the spacing of the ring segments and/or longitudinal members could be closer at the bottom end and relatively farther apart toward the top end of the form.

As noted, the form 100 further comprises a plurality of band clamps 600. The band clamps respectively encircle the circular outer surfaces of the ring assemblies, i.e., one band clamp per ring assembly, and are releasably tightened thereabout. The structure and function of the band clamps 600 are explained with primary reference to FIGS. 3, 4, and 6. Each band clamp 600 comprises a first band 602 having a length approximately equal to half of the circumference of a ring assembly, and a second band 604 formed separately from the first band and also having a length approximately equal to half of the circumference of the ring assembly. Thus, the two bands 602, 604 together have a collective length for extending completely about the circumference of the ring assembly. Alternatively, a single band having a length for extending completely about the circumference of the ring assembly could be used. The bands can comprise any suitably strong, flexible, and substantially inextensible (i.e., non-stretchable) material such as sheet metal or the like.

Each band clamp 600 includes at least one latch 610, i.e., a single latch can be used when a single band is employed as noted above. In the illustrated embodiment having two bands 602, 604, there are two latches 610. Each latch comprises a latch actuator 620 affixed to one end of each metal band and a latch member 630 affixed to the opposite end of each metal band. The metal bands are configured to collectively extend about one of the ring assemblies and to be releasably secured thereabout by engaging the latch actuators 620 with the latch member 630.

In one embodiment, the latches 610 comprise over-center latches as shown. With reference to FIG. 4, each latch actuator 620 comprises a base 622 rigidly affixed to the associated metal band, and a latch handle 624 connected to the base so as to pivot relative to the base about a first pivot axis A1. The latch actuator further comprises a latch bail 626 having a proximal end connected to the latch handle so as to pivot relative to the latch handle about a second pivot axis A2 spaced from the first pivot axis A1. The opposite distal end of the latch bail 626 is engageable with the associated latch member 630 that is rigidly affixed to the opposite end of the other metal band. The pivot axes A1, A2 are positioned relative to each other, and the latch handle 624 is movable through a sufficient range of pivotal motion, so that the pivot axis A2 is able to move from one side of the plane that passes through the first pivot axis A1 and the distal end of the latch bail 626 when engaged with the latch member 630 (as shown in broken lines in FIG. 4), to the other side of said plane (as shown in solid lines in FIG. 4), thereby latching the latch and drawing the latch member 630 toward the first pivot axis A1 so as to tighten the bands about the ring assembly. The second latch 610 is closed in a similar fashion. To open the latches, the latch handles are pivoted to move the second pivot axis A2 to the other side of the plane, which allows the latch bails to be disengaged from the latch members.

While band clamps with latches are illustrated and described in the exemplary embodiment described herein, alternatively the bands can be tightened about the form using other mechanisms such as nuts and bolts engaging brackets secured to the metal bands, or other arrangements.

In operation, the concrete form 100 is used as follows. The form can be transported to the jobsite either in the assembled condition (FIG. 1) or in a disassembled condition in which the band clamps 600 are removed and the four units 200, 300, 400, 500 are stacked together. A significant advantage of the form 100 is that it comprises only four main parts, i.e., the units 200, 300, 400, 500, plus the band clamps, which makes assembly of the form at the jobsite a relatively simple matter. Once at the jobsite, the form (if initially disassembled) can be assembled with basic tools such as a hammer; no specialized tools or skills are needed. To assemble the form, the units 200, 300, 400, 500 are fit together into a generally square tube configuration. Pieces of adhesive tape can be used to temporarily secure the units together so they do not slip relative to each other. The form advantageously can be assembled in a horizontal orientation at or near the location where the concrete column is to be poured. If desired, a specially adapted assembly jig (not shown) can be used for supporting the assembly spaced above the ground so as to facilitate the attachment of the band clamps. The band clamps 600 are wrapped about the ring assemblies and are secured by closing the latches 610. The attachment of the band clamps is accomplished most easily by initially attaching one band clamp about the ring assembly at one end of the form, and then attaching another band clamp about the ring assembly at the opposite end of the form. The form can then be moved and shifted as necessary to attach the remaining band clamps without fear of the units becoming disconnected from one another. Once all band clamps are attached, the assembled form can then be uprighted to a vertical orientation, such as by using a crane or the like, and placed precisely where the column is to be formed. It is also possible to assemble the form in a vertical orientation. The vertically oriented form typically will be braced by an external bracing system (not shown) that holds the form in the desired position and orientation. Concrete is then poured into the top end of the form until the square channel C is substantially filled with concrete. After the concrete has hardened sufficiently, the form is stripped off the column basically by reversing the order of assembly steps described above.

The inner surfaces of the units 200, 300, 400, 500 that directly contact the concrete can be covered with a coating or a layer of polymer film (not shown), if desired, in order to facilitate detaching the units from the hardened concrete, and to serve as a water-resistant liner. When a polymer film is used, the film can be glued or stapled to the inner surfaces. The polymer coating or layer can also serve the function of covering any surface roughness or defects (pits, grooves, etc.) in the concrete-contacting surfaces of the units so that the outer surfaces of the concrete column are smooth. Non-limiting examples of release/liner materials that are useful for these purposes include various polymer films, oils, waxes, and the like.

The concrete form 100 can be reused multiple times. The form 100 as described is useful for making square columns, but as noted, the invention is applicable to columns of various numbers of sides. Thus, an N-sided column can be poured using a form comprising a plurality N of units each having a plate member and a plurality of ring segments and one or more longitudinal members generally as described above.

Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. 

1. A concrete form for pouring a square or rectangular column, comprising: first, second, third, and fourth plate members arranged to form a square or rectangular tube; and a reinforcing framework including a plurality of ring assemblies longitudinally spaced along the tube and interconnected by a plurality of circumferentially spaced longitudinal members, wherein each ring assembly extends circumferentially about the tube and comprises four ring segments each having an inner surface bearing against an outer surface of a respective one of the plate members, and an outer surface formed as a circular arc, the outer surfaces of the four ring segments collectively forming a substantially circular outer surface, and further comprising a plurality of clamps respectively encircling the circular outer surfaces of the ring assemblies and being releasably tightened thereabout.
 2. The concrete form of claim 1, wherein the inner surface of each ring segment is substantially planar and includes at least one notch therein for accommodating one of the longitudinal members such that an inner surface of the longitudinal member is substantially flush with the inner surface of the ring segment.
 3. The concrete form of claim 1, wherein the inner surface of each ring segment is substantially planar and includes a plurality of spaced notches therein for respectively accommodating a plurality of the longitudinal members in the notches such that an inner surface of each longitudinal member is substantially flush with the inner surface of the ring segment.
 4. The concrete form of claim 1, wherein the first plate member and a first plurality of the ring segments and longitudinal members are secured together forming a first unit, the second plate member and a second plurality of the ring segments and longitudinal members are secured together forming a second unit, the third plate member and a third plurality of the ring segments and longitudinal members are secured together forming a third unit, and the fourth plate member and a fourth plurality of the ring segments and longitudinal members are secured together forming a fourth unit, wherein the first through fourth units are configured to releasably mate with one another at respective side edges of the units such that the tube is formed and such that the ring segments of each unit are aligned with the ring segments of the other units.
 5. The concrete form of claim 4, wherein one side edge of each unit defines a rabbet that receives a side edge of an adjacent one of the units so as to form a rabbet joint therebetween.
 6. The concrete form of claim 4, wherein each clamp comprises a band clamp.
 7. The concrete form of claim 6, wherein each band clamp includes a least one metal band and at least one latch.
 8. The concrete form of claim 6, wherein each band clamp includes separate first and second metal bands and first and second latches, the first latch comprising a first latch actuator affixed to one end of the first metal band and a first latch member affixed to one end of the second metal band, the second latch comprising a second latch actuator affixed to the opposite end of the second metal band and a second latch member affixed to the opposite end of the first metal band, the metal bands being configured to extend about one of the ring assemblies and to be secured thereabout by engaging the first latch actuator with the first latch member and the second latch actuator with the second latch member.
 9. The concrete form of claim 8, wherein the latches comprise over-center latches, each latch actuator comprising a base having a latch handle connected thereto so as to pivot about a first pivot axis, and a latch bail having one end connected to the latch handle so as to pivot relative to the latch handle about a second pivot axis spaced from the first pivot axis, an opposite end of the latch bail being engageable with the latch member.
 10. A concrete form for pouring a polygonal column, comprising: a plurality N of plate members arranged to form a polygonal tube having N sides; and a reinforcing framework including a plurality of ring assemblies longitudinally spaced along the tube and interconnected by a plurality of circumferentially spaced longitudinal members, wherein each ring assembly extends circumferentially about the tube and comprises N ring segments each having an inner surface bearing against an outer surface of a respective one of the plate members, and an outer surface formed as a circular arc, the outer surfaces of the N ring segments collectively forming a substantially circular outer surface, and further comprising a plurality of clamps respectively encircling the circular outer surfaces of the ring assemblies and being releasably tightened thereabout.
 11. The concrete form of claim 10, wherein the inner surface of each ring segment is substantially planar and includes at least one notch therein for accommodating one of the longitudinal members such that an inner surface of the longitudinal member is substantially flush with the inner surface of the ring segment.
 12. The concrete form of claim 10, wherein the inner surface of each ring segment is substantially planar and includes a plurality of spaced notches therein for respectively accommodating a plurality of the longitudinal members in the notches such that an inner surface of each longitudinal member is substantially flush with the inner surface of the ring segment.
 13. The concrete form of claim 10, wherein each clamp comprises a band clamp.
 14. The concrete form of claim 13, wherein each band clamp includes a least one metal band and at least one latch.
 15. The concrete form of claim 13, wherein each band clamp includes separate first and second metal bands and first and second latches, the first latch comprising a first latch actuator affixed to one end of the first metal band and a first latch member affixed to one end of the second metal band, the second latch comprising a second latch actuator affixed to the opposite end of the second metal band and a second latch member affixed to the opposite end of the first metal band, the metal bands being configured to extend about one of the ring assemblies and to be secured thereabout by engaging the first latch actuator with the first latch member and the second latch actuator with the second latch member.
 16. The concrete form of claim 15, wherein the latches comprise over-center latches, each latch actuator comprising a base having a latch handle connected thereto so as to pivot about a first pivot axis, and a latch bail having one end connected to the latch handle so as to pivot relative to the latch handle about a second pivot axis spaced from the first pivot axis, an opposite end of the latch bail being engageable with the latch member.
 17. The concrete form of claim 10, wherein the plate members, ring segments, and longitudinal members are non-metallic. 